Greene County historian David Dorpfeld explains the provenance of one of Greene County's odder town names in the Daily Mail:
Coxsackie is an interesting name to speculate about. I recently talked to a woman who told me that, as a teenager, upon hearing she was moving Coxsackie said to her parents, “I have heard of Kawasaki, but never Coxsackie.” It is indeed unusual. The wording of the original deed for the Bronck homestead’s land in the town of Coxsackie is included in “Beers History of Greene County New York.” It was signed with an X by two Indian sellers, Sisketas and Slachemoes, and refers to the area as Koxhackung. It is believed that the Indians knew the location as “Owl Place” or “Hoot Owl Place.” Over the years various spellings can be found such as Koxhaexy, Koixhacking, Kockhachingh, Koxhacxy, Kaksakee, and Coxhacky. Some time before the start of the American Revolution the present spelling was settled upon.